/Engine/Source/Developer/ShaderFormatOpenGL/Public/ShaderFormatOpenGL.h
Create the language spec
virtual [FGlslLanguageSpec](API\Developer\ShaderFormatOpenGL\FGlslLanguageSpec) * CreateLanguageSpec ( [GLSLVersion](API\Developer\ShaderFormatOpenGL\GLSLVersion) Version, bool bDefaultPrecisionIsHalf )